Organic-inorganic hybrid polymer materials with compositional gradient, and processes for preparing the same

ABSTRACT

According to the present invention, organic-inorganic hybrid polymer materials with compositional gradient, and processes for preparing the same are provided. In the organic-inorganic hybrid polymer materials with compositional gradient, formation of cracks, removal of surface, or deformation such as warp and distortion, under heat shock or upon aging, hardly occurs. The organic-inorganic hybrid polymer materials with compositional gradient are comprised of an organic polymer component and a metal oxide component which are covalently bonded each other, characterized in that concentration of the organic polymer component, or of the metal oxide component is increased or decreased in the direction of thickness of the material.

FIELD OF THE INVENTION

The present invention relates to a polymeric material which is usefulfor various kinds of plastic materials, adhesives, and coatingmaterials.

BACKGROUND OF THE INVENTION

Various inorganic materials are now widely employed for industrial usein consideration of both property of the material and requirement of theuse. A silicic ceramic material, for example silicon carbide, or siliconnitride, is excellent in mechanical strength, chemical resistance, andthermal stability. A silicic material such as silicon oxide, andtitanium oxide additionally has excellent optical properties.

Since the inorganic material is hard and brittle, it is generallydifficult to mold and to process the inorganic material. The inorganicmaterial is also poor in adhesiveness with an organic material, andtherefore the use is generally restricted.

On the other hand, the organic polymer is flexible and is easilyprocessed. However, their hardness and thermal stability are largelyinferior to those of the inorganic material.

Therefore, there is great demand for the material which is able tocomplement to each other in their properties, and is able to make theuse of the respective advantages thereof.

For solving the problem, a reinforcing filler such as glass fibers,glass beads, silica, alumina, and calcium carbonate is usually includedor dispersed in an organic polymer material. Such an organic-inorganiccomposite material has been investigated in order to add excellentproperties of an inorganic material such as hardness, strength, heatresistance, and weather resistance to an organic polymer material.However, an inorganic material is generally immiscible with an organicpolymer material, and it is not easy to control a dispersion state ofthe inorganic material microscopically.

When an inorganic material is included in an organic polymer material, alarge quantity of the inorganic material have to be dispersed finely andhomogeneously in an organic polymer material in order to modify theorganic material effectively. Whereas, if the particle size of aninorganic material becomes small, the inorganic material becomes easy toagglomerate in an organic polymer material. Therefore it is difficult todisperse fine particles of inorganic material into an organic polymermaterial at random with aggregation.

Furthermore, there is a maximum limit of an addition amount of theinorganic material. Thus, if the addition amount is increased beyond themaximum limit, molding property of the resulting composite materialbecomes poor, fracture or cracks may easily occur in the resultingcomposite material.

As described above, the method of blending or combining an inorganicmaterial with an organic polymer, is not sufficient, and it is desiredto provide a novel means for providing a high-performanceorganic-inorganic composite material.

As a means for solving the problem, organic-inorganic hybrid polymermaterials are studied. The organic-inorganic hybrid polymer material isthe polymer material in which an inorganic element such as Si, Ti, andZr is incorporated in a backbone frame of an organic material. Thematerial is generally prepared by using sol-gel reaction with a metalalkoxide compound. The inorganic element is covalently bonded to thebackbone frame of the organic material, and a dispersed state of theinorganic element becomes molecularscopically homogeneous throughout thematerial.

Japanese Patent Kokai Publication No. 43679/1993, 86188/1993,104710/1996, 104711/1996, Macromolecules, vol. 25, page 4309, 1992, J.Inorg. Organomet. Polym., vol. 5, page 4, 1995, J. Appl. Polym. Sci.vol. 58, page 1263, 1995, and the like disclose an organic-inorganichybrid polymer material in which a vinyl polymer or a hydrophilicpolymer is employed as an organic polymer material.

On the other hand, functionally graded materials have recently beeninvestigated in the art. The functionally graded materials is thehigh-performance material in which a compositional ratio or componentdistribution is gradiently altered throughout the material. Thefunctionally graded materials is expected to be applied in the art ofaircraft, aerospace, nuclear fusion, electronics, medical, and the like.Although functionally graded materials have heretofore been mainlyinvestigated by using metal materials or ceramics, functionally gradedmaterials by using organic polymers are also recently reported.

For example, Japanese Patent Kokai Publication No. 138780/1993 describesa plastic molded product of which heat resistance is gradientlydistributed, prepared by radically curing plural layers, each of thelayers being composed of radically polymerizable vinyl polymers havingdifferent viscosities.

Japanese Patent Kokai Publication No. 57009/1994 describes a polyolefinof which crosslinking degree is gradient, prepared by mixing, fusing andmolding with changing the ratio of an alkenyl silane/olefine copolymercomponent to a catalyst component. Japanese Patent Kokai Publication No.176325/1997 describes a material in which a silicon or oxygen content isgradient, prepared by heat treating a polymer having a Si-H bond andalkyne.

Japanese Patent Kokai Publication No. 283425/1996 describes an examplefor applying the technique of the functionally graded materials to anorganic-inorganic composite material. There is described in thepublication, a polymer material with compositional gradient in whichmetal oxide particles are dispersed in an organic polymer. Thecomponent-gradient polymer material is prepared by the processcomprising: applying a homogeneous solution of a heat curable resincomposition and silicone alkoxide onto a substrate; hydrolyzing andpolycondensing the silicone alkoxide under a specific condition; andcuring the heat curable resin. However, the metal oxide particles andthe organic polymer are not covalently bonded in the polymer material,and the polymer material with compositional gradient disclosed herein isclassified into a dispersed type organic-inorganic composite material.

Further, a metal oxide content of the polymer material withcompositional gradient is up to about 60%. Such a level of the metaloxide content is insufficient as functionally graded materials. On theother hand, such an amount is thought to be about a maximum limit fordispersing an inorganic material into an organic polymer material.Therefore, it is difficult to further increase an amount of metal oxideparticles dispersed in the component-gradient polymer material.

The technical effects of the functionally graded materials are generallyheat shock resistance, warpage resistance, and the like. However,Japanese Patent Kokai Publication No. 283425/1996 does not refer to sucha properties.

SUMMARY OF THE INVENTION

According to the present invention, organic-inorganic hybrid polymermaterials with compositional gradient, and processes for preparing thesame are provided. In the organic-inorganic hybrid polymer materialswith compositional gradient, formation of cracks, removal of surface, ordeformation such as warp and distortion, under heat shock or upon aging,hardly occurs.

The present invention provides organic-inorganic hybrid polymermaterials with compositional gradient composed of an organic polymercomponent and a metal oxide component which are covalently bonded eachother, characterized in that concentration of the organic polymercomponent, or of the metal oxide component is increased or decreased inthe direction of thickness of the material.

The organic-inorganic hybrid polymer materials with compositionalgradient may generally be prepared by the process comprising the stepsof:

providing a substrate having a surface; and

applying plural layers of solutions or wet gels which comprises at leastone of an organic polymer and a metal alkoxide, on the surface of thesubstrate, so that concentration of the organic polymer component, or ofthe metal oxide component in the resulting material, is increased ordecreased in the direction of thickness of the material.

Preferably, the organic-inorganic hybrid polymer materials withcompositional gradient may be prepared by the process comprising thesteps of:

(i) providing a substrate having a surface;

(ii) applying thereon a solution or a wet gel which comprises at leastone of an organic polymer and a metal alkoxide at a certaincompositional ratio;

(iii) applying thereon a solution or a wet gel which comprises at leastan organic polymer or a metal alkoxide in altering a compositional ratioof the solution or the wet gel so that concentration of the organicpolymer component, or of the metal oxide component in the resultingmaterial, is increased or decreased in the direction of thickness of thematerial.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a SEM photograph which shows cross-section ofsilica-polycarbonate component-gradient polymer film coated on a glasssubstrate, with Si element concentration curve.

FIG. 2 is a SEM photograph which shows cross-section ofsilica-polycarbonate component-gradient polymer film coated on a PCsubstrate, with Si element concentration curve.

FIG. 3 is a SEM photograph which shows cross-section of PC film coatedon a glass substrate, with Si element concentration curve.

FIG. 4 is a SEM photograph which shows cross-section of silica filmcoated on a PC substrate, with Si element concentration curve.

In the drawings, 101, 201, 301, and 401 represent a boundary part of thesubstrate and the film, and 102, 202, 302, and 402 show a surface partof the film.

DETAILED DESCRIPTION OF THE INVENTION Organic Polymer (A)

Organic polymer (A) of the present invention is a polymer which has areactive functional group with metal alkoxide compound (B). Organicpolymer (A) may be those prepared by any procedure.

As a backbone frame of organic polymer (A), thermoplastic resins orthermoplastic elastomer precursors such as polyethylene, polypropylene,vinyl chloride resin, polystyrene, methyl methacrylate resin, polyamide,polyacetal, polycarbonate, polyester, polyphenylene ether, polymethylpentene, polysulfone, polyether sulfone, polyphthalamide, polyphenylenesulfide, polyarylate, polyimide, polyether imide, and polyether ketone;and thermosetting resin precursors such as phenol resin, epoxy resin,acrylic resin, melamine resin, alkyd resin, and urea resin.

Among these, the thermoplastic resins are preferred, and engineeringplastics such as polyamide, polyacetal, polycarbonate, polysulfone, andpolyarylate are more preferred due to their high performance.

The backbone frame of organic polymer (A) may be one component selectedfrom the above described polymers or precursors, or may be a copolymerthereof. Organic polymer (A) may be a mixture of the plural polymers,and it may be linear or branched. Organic polymer (A) is preferablysoluble or swellable in a solvent such as halogenated hydrocarbon,ether, alcohol, and aprotic polar solvent, and preferably has a numberaverage molecular weight of from 500 to 50000, more preferably 1000 to15000. The number average molecular weight of organic polymer (A) maygenerally be measured by the GPC method.

A functional group of organic polymer (A) can react with a metalalkoxide compound (B). The specific functional group of organic polymer(A) includes, but not limited to, an alkoxymetal group, a hydroxylgroup, an amino group, a carboxyl group. An alkoxymetal group isparticularly preferred.

The functional group equivalent of organic polymer (A) is generally 1 to100, preferably 1 to 50, more preferably 2 to 10. If the functionalgroup equivalent of organic polymer (A) is less than 1, performance ofthe resulting material may become poor, and is more than 100, theresulting material may become fragile.

Metal Alkoxide Compound (B)

Metal alkoxide compound (B) of the present invention is not limited to,and any class of them may be used. Preferred examples of metal alkoxidecompound (B) are those represented by the formula (1):

A_(p)M  (1)

wherein A represents an alkoxy group having 1 to 8, preferably 1 to 4carbon atoms;

M represents a metal element selected from the group composed of Si, Ti,Zr, Fe, Cu, Sn, B, Al, Ge, Ce, Ta, and W, preferably the group composedof Si, Ti, and Zr; and

p represents an integer of 2 to 6.

Specific examples of metal alkoxide compound (B) includetetra-alkoxysilanes such as tetramethoxysilane, tetraethoxysilane,tetraisopropoxysilane, and tetrabutoxysilane;

titanium tetra-alkoxides such as titanium tetra-n-propoxide, titaniumtetra-iso-propoxide, and titanium tetrabutoxide;

zirconium tetra-alkoxides such as zirconium tetra-n-propoxide, zirconiumtetra-iso-propoxide, and zirconium tetrabutoxide; and

metal alkoxides such as copper dimethoxide, barium diethoxide, borontrimethoxide, gallium triethoxide, aluminium tributoxide, germaniumtetraethoxide, lead tetrabutoxide, tantalum penta-n-propoxide, andtungsten hexaethoxide.

The other examples of metal alkoxide compound (B) are those representedby the formula (2):

R_(k)A₁M(R′_(m)X)_(n)

wherein R represents a hydrogen atom, an alkyl group having 1 to 12,preferably 1 to 5 carbon atoms, or a phenyl group,

A represents an alkoxy group having 1 to 8, preferably 1 to 4 carbonatoms,

M represents a metal element selected from the group composed of Si, Ti,Zr, Fe, Cu, Sn, B, Al, Ge, Ce, Ta, and W, preferably the group composedof Si, Ti, and Zr,

R′ represents an alkylene group or an alkylidene group having 1 to 4,preferably 2 to 4 carbon atoms,

X represents a functional group selected from the group composed of anisocyanato group, an epoxy group, a carboxyl group, an acid halidegroup, an acid anhydride group, an amino group, a thiol group, a vinylgroup, a methacryl group, and a halogen atom, and

k represents an integer of 0 to 5, l represents an integer of 1 to 5, mrepresents 0 or 1, n represents an integer of 0 to 5.

Specific examples of metal alkoxide compound (B) of which metal issilicone, include (alkyl)alkoxysilanes such as trimethoxysilane,triethoxysilane, tri-n-propoxysilane, dimethoxysilane, diethoxysilane,di-iso-propoxysilane, monomethoxysilane, monoethoxysilane,monobutoxysilane, methyldimethoxysilane, ethyldiethoxysilane,dimethylmethoxysilane, di-iso-propylisopropoxysilane,methyltrimethoxysilane, ethyltriethoxysilane,n-propyltri-n-propoxysilane, butyltributoxysilane,dimethyldimethoxysilane, diethyldiethoxysilane,di-iso-propyldi-iso-propoxysilane, dibutyldibutoxysilane,trimethylmethoxysilane, triethylethoxysilane,tri-n-propyl-n-propoxysilane, tributylbutoxysilane,phenyltrimethoxysilane, diphenyldiethoxysilane, andtriphenylmethoxysilane;

(alkyl)alkoxysilanes having an isocyanato group such as3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane,2-isocyanato-ethyltriethoxysilane,2-isocyanato-ethyltri-n-propoxysilane,2-isocyanato-ethylethyldibutoxysilane,3-isocyanatopropylmethyldimethoxysilane,3-isocyanatopropylethyldiethoxysilane,3-isocyanatopropyldimethyl-iso-propoxysilane,3-isocyanatopropyldiethylethoxysilane,2-isocyanato-ethyldiethylbutoxysilane,di(3-isocyanatopropyl)diethoxysilane,di(3-isocyanatopropyl)methylethoxysilane, andethoxytri-isocyanatosilane;

(alkyl)alkoxysilanes having an epoxy group such as3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane,3-glycidoxypropylmethyldimethoxysilane,3-glycidoxypropylmethyldiethoxysilane,3-glycidoxypropyldimethylethoxysilane,2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and3,4-epoxybutyltrimethoxysilane;

(alkyl)alkoxysilanes having a carboxyl group such ascarboxymethyltriethoxysilane, carboxymethylethyldiethoxysilane, andcarboxyethyldimethylmethoxysilane;

alkoxysilanes having an acid anhydride group such as3-(triethoxysilyl)-2-methylpropylsuccinic anhydride;

alkoxysilanes having a acid halide group such as2-(4-chlorosulfonylphenyl)ethyltriethoxysilane;

(alkyl)alkoxysilanes having an amino group such as3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane,N-2-(aminoethyl)-3-aminopropyltriethoxysilane,N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, andN-phenyl-3-aminopropyltrimethoxysilane;

(alkyl)alkoxysilanes having a thiol group such as3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane,2-mercaptoethyltriethoxysilane, and3-mercaptopropylmethyldimethoxysilane;

(alkyl)alkoxysilanes having a vinyl group such as vinyltrimethoxysilane,vinyltriethoxysilane, and vinylmethyldiethoxysilane;

(alkyl)alkoxysilanes having a methacryl group such as3-methacryloxypropyltrimethoxysilane,3-methacryloxypropyltriethoxysilane, and3-methacryloxypropylmethyldimethylsilane;

(alkyl)alkoxysilanes having a halogen atom such astriethoxyfluorosilane, 3-chloropropyltrimethoxysilane,3-bromopropyltriethoxysilane, and 2-chloroethylmethyldimethoxysilane;and

alkylalkoxysilanes employing an alkoxy group as a functional group suchas isopropyltri-isopropoxysilane, and tri-isopropylisopropoxysilane.

Substantially the same compounds as described above except that themetal element other than silicon, for example Ti, Zr, Fe, Cu, Sn, B, Al,Ge, Ce, Ta, or W is used, are also included in the scope of metalalkoxide compound (B) of the present invention.

Specific examples of such compounds includemonoisocyanatotrialkoxymetals such as2-isocyanato-ethyltripropoxyzirconium, and2-isocyanato-ethyltributoxytin;

monoisocyanatodialkoxymetals such as3-isocyanatopropylmethyldi-isopropoxytitane,2-isocyanato-ethylethyldipropoxyzirconium,2-isocyanato-ethylmethyldibutoxytin, andisocyanatomethyldimethoxyaluminium;

monoisocyanatomonoalkoxymetals such as3-isocyanatopropyldimethylisopropoxytitane,2-isocyanato-ethyldiethylpropoxyzirconium,2-isocyanato-ethyldimethylbutoxytin, andisocyanatomethylmethylmethoxyaluminium;

metal alkoxides employing an epoxy group as a functional group such as3-glycidoxypropyltriisopropoxytitane,3-glycidoxypropylmethyldi-isopropoxytitane,3-glycidoxypropyldimethylisopropoxytitane,3,4-epoxybutyltripropoxyzirconium,3,4-epoxybutylmethyldipropoxyzirconium,3,4-epoxybutyldimethylpropoxyzirconium, and1-(3,4-epoxycyclohexyl)ethyltriethoxytin.

Metal alkoxide compound (B) may be used alone or in combination of notless than two thereof. The metal alkoxide compound which includes notless than two kinds of metal such as Mg[Al(iso-OC₃H₇)₄]₂,Ba[Zr₂(OC₂H₅)₉]₂, (C₃H₇O)₂Zr[Al(OC₃H₇)₄]₂, or the oligomer type metalalkoxide compound which includes not less than two repeating unites inthe molecule such as tetramethoxysilane oligomer, tetraethoxysilaneoligomer are also employed. The alkoxy group of metal alkoxide compound(B) may be an acetoxy group.

Organic-inorganic Hybrid Polymer Materials with Compositional Gradient

Organic-inorganic hybrid polymer materials is prepared by the processof: a solution of organic polymer (A) which has a reactive functionalgroup with metal alkoxide compound (B), and metal alkoxide compound (B)is prepared; and the solution is hydrolyzed and polycondensed on thesol-gel reaction.

In preparing the organic-inorganic hybrid polymer material, mixtures ofthe organic polymer (A) and the metal alkoxide compound (B), of whichcompositional ratio being each gradiently altered within the range of0/10 to 10/0, are prepared; the solutions are applied to form amultilayer in order of the compositional ratio; and the layers arehydrolyzed and polycondensed on the sol-gel reaction to obtain theobjective organic-inorganic hybrid polymer materials with compositionalgradient.

A content of the organic polymer component or the metal alkoxidecomponent in the organic-inorganic hybrid polymer materials withcompositional gradient is preferably not more than 30% by weight at thelowest region, and not less than 70% by weight at the highest region.

Examples for application of the organic-inorganic hybrid polymermaterials with compositional gradient include a materials of coating,thread, film, and molded articles having a shape of ball, block, and thelike.

Organic-inorganic hybrid polymer material with compositional gradient ofthe present invention basically has an internal structure in which acompositional ratio of an organic polymer component and a metal alkoxidecomponent is constant in the parallel direction with the surface of thematerial, and the compositional ratio is gradiently altered, in thedirection of thickness of the material, in the perpendicular directionto a surface of the material, or in the direction of from the surfacetoward the inside of the material. Therefore, the organic-inorganichybrid polymer materials with compositional gradient of the presentinvention is different from those which contain therein adiscontinuously altered concentration due to random coagulation, orphase separation; or different from a coated film which has uniformconcentration throughout the material.

Throughout the specification, the hydrolysis and polycondensation on thesol-gel process means the reaction process in which a polymer having analkoxymetal group reacts with water, the alkoxymetal group converts to ahydroxyl group, and the hydroxyl group is simultaneously polycondensedwith an adjacent hydroxymetal group (e.g., —Si(OH)₃) or an adjacentalkoxymetal group by dehydration or elimination of alcohol to formthree-dimensional crosslinkage composed of inorganic covalent bond. Thepolycondensation reaction typically occurs due to dehydration betweentwo hydroxymetal groups, but the dehydration may occur between ahydroxymetal group and a functional group having an active hydrogen suchas the other hydroxyl group, an amino group, and a carboxyl group.

The water may be added to the reaction process in the amount sufficientfor converting all of the alkoxy group to the hydroxyl group. Otherwise,water present in the reaction mixture, or moisture of an atmosphere maybe utilized. The reaction is preferably conducted at from roomtemperature to 100° C. for 0.5 to 24 hours. An acidic catalyst such ashydrochloric acid, sulfonic acid, acetic acid, benzenesulfonic acid, andp-toluenesulfonic acid, or a basic catalyst such as sodium hydroxide,potassium hydroxide, ammonia, triethylamine, piperidine, and1,8-diazabicyclo-[5,4,0]-7-undecene (DBU), may also be employed.

The resulting material may further be heated at 50 to 500° C., for 5minutes to 48 hours in order to surely proceed the polycondensationreaction and to form hard crosslinkage.

The internal structure of organic-inorganic hybrid polymer materialswith compositional gradient of the present invention is microscopicallyuniform and the compositional ratio of an organic polymer component or ametal alkoxide component is gradiently altered in the direction ofthickness of the material, and the processes for preparing the materialare not limited.

However, an example of the process for preparing the material is asfollows. The first mixed composition including organic polymer (A) andmetal alkoxide compound (B) in a certain compositional ratio isprepared. The first mixed composition is then hydrolyzed to obtain thefirst partially condensed wet gel. The first partially condensed wet gelis applied on a surface of a substrate to form the first layer.

The second mixed composition including organic polymer (A) and metalalkoxide compound (B), the compositional ratio of which is slightlychanged from the first mixed composition, is prepared. The second mixedcomposition is hydrolyzed to obtain the second partially condensed wetgel. The second partially condensed wet gel is applied on a surface ofthe first layer. The procedures for forming the layer are thenrepeatedly conducted. When the layers of the compositions are formed,they are then completely hydrolyzed and polycondensed.

Organic-inorganic hybrid polymer materials with compositional gradientprepared by the process has an internal structure in which the organicpolymer component or the metal alkoxide component are microscopicallyuniform, covalently bonded, and the compositional ratio thereof isgradiently altered, in the direction of thickness of the material, inthe perpendicular direction to a surface of the material, or in thedirection of from the surface toward the inside of the material.Therefore, formation of cracks, removal of surface, or deformation suchas warp and distortion, under heat shock or upon aging, hardly occurs inthe organic-inorganic hybrid polymer materials with compositionalgradient.

Examples of the solvent employed for the sol-gel reaction include ahydrocarbon solvent such as benzene, toluene, xylene, ethyl benzene, andn-hexane; a halogenated hydrocarbon solvent such as carbontetrachloride, chloroform, dichloromethane, chloroethane,dichloroethane, chlorobenzene, dichlorobenzene, and trichlorobenzene; anether solvent such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, diethylether, and dibutyl ether; a ketone solvent such as acetone, methyl ethylketone, methyl isobutyl ketone, and cyclohexanone, but is not limited tothese examples. Generally, a polar solvent such as an alcoholic solventis employed.

The metal selected from the group composed of Si, Ti, Zr, Fe, Cu, Sn, B,Al, Ge, Ce, Ta, and W, and a metal compound thereof such as metal oxide,metal complex, metal salt, and the like may further be employed in thehydrolysis and polycondensation reaction of the present invention, inview of further improving strength, hardness, weather resistance,chemical resistance, flame resistance, static resistance of theresulting material; for newly supplying the performance to the material;or for controlling the inorganic content or the crosslinking density ofthe material.

An anti-drying agent such as formamide, dimethylformamide, dioxane,oxalic acid, or the other additives such as acetyl acetone, and the likemay be included in the reaction mixture for the hydrolysis andpolycondensation reaction of the present invention for preventing fromforming the clack during the drying process.

In organic-inorganic hybrid polymer materials with compositionalgradient of the present invention, the properties of an inorganicmaterial such as heat resistance, weather resistance, surface hardness,rigidity, water resistance, chemical resistance, stain resistance,mechanical strength, flame retardant, and the like, are suitablysupplied to an organic polymer material. In the opposite word, theproperties of an organic material such as impact resistance, softness,easy-processable, and the like, are suitably supplied to an inorganicpolymer material.

In addition, formation of cracks, removal of surface, or deformationsuch as warp and distortion, under heat shock or upon aging, hardlyoccurs in the organic-inorganic hybrid polymer materials withcompositional gradient, because the compositional ratio of an organicpolymer component or a metal alkoxide component is gradiently altered.

Therefore, organic-inorganic hybrid polymer materials with compositionalgradient of the present invention may be coated on a plastic material sothat the organic polymer content is decreased and the metal alkoxidecontent is increased from the plastic surface toward the polymermaterial surface, to obtain a plastic material the surface of which isexcellent in hardness, abrasive resistance, chemical resistance,pollution resistance, heat resistance and the like.

Otherwise, organic-inorganic hybrid polymer materials with compositionalgradient of the present invention may be coated on a glass or a metalmaterial so that the metal alkoxide content is decreased and the organicpolymer content is increased from the glass surface toward the polymermaterial surface, to obtain a glass or a metal material the surface ofwhich is excellent in impact resistance, and hard to be broken. Flyingof splinters is inhibited even if the the glass or the metal materialsis broken.

TECHNICAL EFFECTS OF THE INVENTION

Organic-inorganic hybrid polymer materials with compositional gradientis provided in which an organic polymer and an metal oxide arecovalently bonded, which is suitable for use in a high performance and ahighly functional plastic materials, a plastic molded article or film, asealing agent, an adhesive agent, a binder for a coating, a constructionmaterials, an optical materials, an additive for a resin, a surfacemodifying agent, a hard coating agent, an electric or an electronicmaterials, a medical materials, or a filler, and the like.

EXAMPLES

The present invention is illustrated by the following examples which,however, are not to be construed as limiting the present invention totheir details.

Preparation Example 1

70.0 g of polycarbonate diol (PC diol) having a number average molecularweight of 6600, and a hydroxyl group equivalent of 1.6 was dissolvedinto 500 mL of chloroform. To the solution was added 7.9 g of3-isocyanatopropyltriethoxysilane (IPTES), heated with refluxing for 15hours, and cooled to room temperature. The reaction mixture was dropwiseadded to 7 L of methanol to precipitate the reaction product. Theprecipitated substance was filtered off, washed with methanol, and driedin vacuo (97% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolycarbonate in which an alkoxysilyl group is introduced at the bothends of the polycarbonate (PCS). The alkoxysilyl group equivalent of thereaction product was 1.6. The number average molecular weight of thereaction product was determined to be 7500 by GPC measurement.

The detailed conditions for determining the molecular weight are asfollows.

Apparatus Model HLC8020 made by Tosoh Corp. Column KF-806L × 2 andKF-803L × 1 (three columns were coupled) made by Showadenko Co., Ltd.Pre-column KF-2000 made by Showadenko Co., Ltd. Carrier THF Temperature40° C. Flow rate 1.0 ml/min. Detector Refractometer Recorder ModelSC-8020 made by Tosoh Corp. Conversion Polystyrene standard

Preparation Example 2

70.0 g of PC diol having a number average molecular weight of 3900, anda hydroxyl group equivalent of 1.8 was 5 dissolved into 500 mL ofchloroform. To the solution was added 13.3 g of IPTES, heated withrefluxing for 10 hours, and cooled to room temperature. The reactionmixture was dropwise added to 7 L of methanol to precipitate thereaction product. The precipitated substance was filtered 10 off, washedwith methanol, and dried in vacuo (97% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolycarbonate in which an alkoxysilyl group is introduced at the bothends of the polycarbonate (PCS). The alkoxysilyl group equivalent of thereaction product was 1.8. The number average molecular weight of thereaction product was determined to be 4400 by GPC measurement.

Preparation Example 3

17.5 g of polyphenylene ether diol having a number average molecularweight of 3500, and a hydroxyl group equivalent of 2.0 was dissolvedinto 200 mL of chloroform. To the solution was added 4.8 g of IPTES,heated with refluxing for 10 hours, and cooled to room temperature. Thereaction mixture was dropwise added to 2 L of methanol to precipitatethe reaction product. The precipitated substance was filtered off,washed with methanol, and dried in vacuo (95% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolyphenylene ether in which an alkoxysilyl group is introduced at theboth ends of the polyphenylene ether (PPS). The alkoxysilyl groupequivalent of the reaction product was 2.0. The number average molecularweight of the reaction product was determined to be 4300 by GPCmeasurement.

Preparation Example 4

26.0 g of polysulfone diol having a number average molecular weight of5200, and a hydroxyl group equivalent of 1.7 was dissolved into 300 mLof chloroform. To the solution was added 3.5 g of IPTES, heated withrefluxing for 11 hours, and cooled to room temperature. The reactionmixture was dropwise added to 3 L of methanol to precipitate thereaction product. The precipitated substance was filtered off, washedwith methanol, and dried in vacuo (96% yield)

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolysulfone in which an alkoxysilyl group is introduced at the both endsof the polysulfone (PSS). The alkoxysilyl group equivalent of thereaction product was 1.7. The number average molecular weight of thereaction product was determined to be 6000 by GPC measurement.

Preparation Example 5

30.5 g of polyarylate diol having a number average molecular weight of6100, and a hydroxyl group equivalent of 1.6 was dissolved into 300 mLof chloroform. To the solution was added 3.2 g of IPTES, heated withrefluxing for 15 hours, and cooled to room temperature. The reactionmixture was dropwise added to 3 L of methanol to precipitate thereaction product. The precipitated substance was filtered off, washedwith methanol, and dried in vacuo (96% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolyarylate in which an alkoxysilyl group is introduced at the both endsof the polyarylate (PAS). The alkoxysilyl group equivalent of thereaction product was 1.6. The number average molecular weight of thereaction product was determined to be 6700 by GPC measurement.

Preparation Example 6

14.0 g of 1,4-hydrogenated polybutadiene diol having a number averagemolecular weight of 2800, and a hydroxyl group equivalent of 2.3 wasdissolved into 150 mL of chloroform. To the solution was added 4.3 g ofIPTES, heated with refluxing for 8 hours, and cooled to roomtemperature. An organic solvent and a low molecular weight compound weredistilled out by using an evaporator (99% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedhydrogenated polybutadiene in which an alkoxysilyl group is introducedat the both ends of the hydrogenated polybutadiene (HPBS). Thealkoxysilyl group equivalent of the reaction product was 2.1. The numberaverage molecular weight of the reaction product was determined to be3500 by GPC measurement.

Preparation Example 7

14.5 g of polyester diol having a number average molecular of 2900, anda hydroxyl group equivalent of 2.0 was dissolved into 150 mL ofchloroform. To the solution was added 4.0 g of IPTES, heated withrefluxing for 24 hours, and cooled to room temperature. An organicsolvent and a low molecular weight compound were distilled out by usingan evaporator (99% yield).

¹H-NMR spectrum showed that the reaction product was alkoxysilylatedpolyester in which an alkoxysilyl group is introduced at the both endsof the polyester (PES). The alkoxysilyl group equivalent of the reactionproduct was 1.9. The number average molecular weight of the reactionproduct was determined to be 3400 by GPC measurement.

Example 1

A mixed composition containing the PCS having a number average molecularweight of 7500 prepared in Preparation Example 1 and tetraethoxysilane(TEOS) in the ratio by weight shown in Table 1 was hydrolyzed intetrahydrofuran (THF) by using 1N aqueous hydrochloride at roomtemperature to obtain solutions No. 1 to 5.

TABLE 1 Amounts of Components Employed for Preparing Wet Gel PCS/TEOSPCS TEOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7002 25/75 0.5 1.5 13 530 3 50/50 1.0 1.0 15 370 4 75/25 1.5 0.5 18 200 5100/0  2.0 0 20 30

The solutions of Table 1 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5, and a 10% dichloromethanesolution of a polycarbonate resin having a number average molecularweight of 36000, commercially available from Mitsubishi EngineeringPlastics K.K. as the trade name of “IUPILON”, was then spin coatedthereon in the same manner.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 1 minute, and the next solution was coated, inconducting the coating steps. The transparent coated glass substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polycarbonate component-gradientfilm (80 μm in film thickness).

Infrared analysis was conducted on a surface of the resultingsilica/polycarbonate component-gradient film. Peaks which belong to a PCcomponent such as a large peak of a carbonate group at about 1770 cm⁻¹are indicated, but there are no peaks which belong to a silicacomponent.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a glass surfacethrough a film surface, and Si element was not detected on the filmsurface.

FIG. 1 is a SEM photograph which shows cross-section ofsilica-polycarbonate component-gradient film coated on a glasssubstrate, with Si element concentration curve. In the drawing, 101shows a boundary part of the glass substrate and the film, and 102 showsa surface part of the film.

The Si element concentration curve of FIG. 1 indicates that a silicacomponent is present in quantity near by the glass surface and apolycarbonate (PC) component is not present, whereas, a silica componentis not present near by the film surface and is almost a PC component. Itis expected that the PC component also forms a component-gradientstructure, because the silica component forms a component-gradientstructure.

The results of the IR analysis indicate that Si element is not presentin the region near by the film surface, the results of Si elementalanalysis by using SEM indicate that intensity of Si element near by theglass surface is equal to that of glass. Therefore, a compositionalratio of the silica component to the PC component is gradient in therange of from 10/0 to 0/10, throughout the film.

IR analysis was conducted according to the ATR method by using the modelIMPACT 400M commercially available from Nicore Japan K.K. SEMobservation was conducted by using the model JNM-EX270 commerciallyavailable from JEOL.

The results of heat shock test of this film were shown in Table 8.

Example 2

A transparent silica/polycarbonate component-gradient film was preparedaccording to substantially the same manner as described in Example 1,except that when one solution was coated, the coated layer was heattreated at 1500° C. for 30 minutes and allowed to cool, and the nextsolution was coated (50 μm in film thickness).

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, a concentration of Si elementgradiently decreased from a glass surface through a film surface.Therefore, a compositional ratio of the silica component to the PCcomponent is gradient in the range of from 10/0 to 0/10, throughout thefilm.

The results of heat shock test of this film were shown in Table 8.

Example 3

The solutions of Table 1 were coated on a PC substrate by using a spincoater in the order of No. 5 to 1.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 1 minute, and the next solution was coated, inconducting the coating steps. The transparent coated PC substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polycarbonate component-gradientfilm (60 μm in film thickness).

Infrared analysis was conducted on a surface of the resultingsilica/polycarbonate component-gradient film. Peaks which belong to asilica component such as a peak of Si—O—Si at about 1080 cm⁻¹ areindicated, but there are no peaks which belong to a polycarbonatecomponent such as a peak of carbonate group at about 1770 cm⁻¹.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a film surfacethrough a PC surface, and Si element was not detected near by the PCsubstrate.

FIG. 2 is a SEM photograph which shows cross-section ofsilica-polycarbonate component-gradient film coated on a PC substrate,with Si element concentration curve. In the drawing, 201 shows aboundary part of the PC substrate and the film, and 202 shows a surfacepart of the film.

The Si element concentration curve of FIG. 2 indicates that a silicacomponent is present in quantity near by the film surface and apolycarbonate (PC) component is not present, whereas, a silica componentis not present near by the PC substrate and is almost a PC component. Itis expected that the PC component also forms a component-gradientstructure, because the silica component forms a component-gradientstructure.

The results of the IR analysis and the SEM observation indicate that acompositional ratio of the silica component to the PC component isgradient in the range of from 10/0 to 0/10, throughout the film.

The results of heat shock test and chemical resistance test of this filmwere shown in Table 8 and 9.

Example 4

A transparent silica/polycarbonate component-gradient film was preparedaccording to substantially the same manner as described in Example 3,except that when one solution was coated, the coated layer was heattreated at 100° C. for 30 minutes and allowed to cool, and the nextsolution was coated (60 μm in film thickness)

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, a concentration of Si elementgradiently decreased from the film surface through the PC surface.Therefore, a compositional ratio of the silica component to the PCcomponent is gradient in the range of from 10/0 to 0/10, throughout thefilm.

The results of heat shock test and chemical resistance test of this filmwere shown in Table 8 and 9.

Example 5

A mixed composition containing the PCS having a number average molecularweight of 4400 prepared in Preparation Example 2 and tetramethoxysilaneoligomer (TMOS) commercially available from Mitsubishi Kagaku K.K. asthe trade name of “MKC SILICATE MS-56”, in the ratio by weight shown inTable 2 was hydrolyzed in THF by using 1N aqueous hydrochloride at roomtemperature to obtain solutions No. 1 to 5.

TABLE 2 Amounts of Components Employed for Preparing Wet Gel PCS/TMOSPCS TMOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7202 25/75 0.5 1.5 13 560 3 50/50 1.0 1.0 15 390 4 75/25 1.5 0.5 18 220 5100/0  2.0 0 20 50

The solutions of Table 2 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5, and a 10% dichloromethanesolution of a polycarbonate resin having a number average molecularweight of 36000, commercially available from Mitsubishi EngineeringPlastics K.K. as the trade name of “IUPILON”, was then spin coatedthereon in the same manner.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 1 minute, and the next solution was coated, inconducting the coating steps. The transparent coated glass substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polycarbonate component-gradientfilm (70 μm in film thickness).

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, intensity of Si element near bythe glass surface was equal to that of glass, and Si element is notpresent near by the film surface. Therefore, a compositional ratio ofthe silica component to the PC component is gradient in the range offrom 10/0 to 0/10, throughout the film.

The results of heat shock test of this film were shown in Table 8.

Example 6

A transparent silica/polycarbonate component-gradient film was preparedaccording to substantially the same manner as described in Example 5,except that when one solution was coated, the coated layer was heattreated at 150° C. for 30 minutes and allowed to cool, and the nextsolution was coated (50 μm in film thickness).

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, a concentration of Si elementgradiently decreased from the glass surface through the film surface.Therefore, a compositional ratio of the silica component to the PCcomponent is gradient in the range of from 10/0 to 0/10, throughout thefilm.

The results of heat shock test of this film were shown in Table 8.

Example 7

The solutions of Table 2 were coated on a PC substrate by using a spincoater in the order of No. 5 to 1.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 1 minute, and the next solution was coated, inconducting the coating steps. The transparent coated PC substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polycarbonate component-gradientfilm (70 μm in film thickness).

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, a concentration of Si elementgradiently decreased from the film surface through the PC surface.Therefore, a compositional ratio of the silica component to the PCcomponent is gradient in the range of from 10/0 to 0/10, throughout thefilm.

The results of heat shock test and chemical resistance test of this filmwere shown in Table 8 and 9.

Example 8

A transparent silica/polycarbonate component-gradient film was preparedaccording to substantially the same manner as described in Example 7,except that when one solution was coated, the coated layer was heattreated at 100° C. for 30 minutes and allowed to cool, and the nextsolution was coated (60 μm in film thickness)

Infrared analysis and SEM observation were conducted on the resultingsilica/polycarbonate component-gradient film. Macroscopic phaseseparation was not indicated. Further, a concentration of Si elementgradiently decreased from the film surface through the PC surface.Therefore, a compositional ratio of the silica component to the PCcomponent is gradient in the range of from 10/0 to 0/10, throughout thefilm.

The results of heat shock test and chemical resistance test of this filmwere shown in Table 8 and 9.

Example 9

A mixed composition containing the PPS having a number average molecularweight of 4300 prepared in Preparation Example 3 and tetraethoxysilane(TEOS) in the ratio by weight shown in Table 3, was hydrolyzed in THF byusing 1N aqueous hydrochloride at 50° C. to obtain solutions No. 1 to 5.

TABLE 3 Amounts of Components Employed for Preparing Wet Gel PPS/TEOSPPS TEOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 20 7002 25/75 0.5 1.5 30 540 3 50/50 1.0 1.0 30 390 4 75/25 1.5 0.5 40 240 5100/0  2.0 0 40 90

The solutions of Table 3 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5, and a 10% chloroform solution ofa polyphenylene ether resin having a number average molecular weight of24000, commercially available from Nippon GE Plastics K.K. as the tradename of “N-50-3181”, was then spin coated thereon in the same manner.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 10 minutes, and the next solution was coated, inconducting the coating steps. The transparent coated glass substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polyphenylene ethercomponent-gradient film (40 μm in film thickness).

Infrared analysis was conducted on a surface of the resultingsilica/polyphenylene ether component-gradient film. Peaks which belongto a C—H bond or an aromatic ring of polyphenylene ether such as peaksat about 1470 cm⁻¹, 2920 cm⁻¹, and 1600 cm⁻¹ are indicated, but thereare no peaks which belong to a silica component.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a glass surfacethrough a film surface, and Si element was not detected on the filmsurface.

The results of the IR analysis and the Si elemental analysis by usingSEM indicate that a silica component is present in quantity near by theglass surface and a polyphenylene ether component is not present,whereas, a silica component is not present near by the film surface andis almost a polyphenylene ether component. Therefore, a compositionalratio of the silica component to the polyphenylene ether component isgradient in the range of from 10/0 to 0/10, throughout the film.

Example 10

A mixed composition containing the PSS having a number average molecularweight of 6000 prepared in Preparation Example 4 and tetramethoxysilane(TMOS) in the ratio by weight shown in Table 4, was hydrolyzed in THF byusing 1N aqueous hydrochloride at room temperature to obtain solutionsNo. 1 to 5.

TABLE 4 Amounts of Components Employed for Preparing Wet Gel PSS/TMOSPSS TMOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7202 25/75 0.5 1.5 15 560 3 50/50 1.0 1.0 15 390 4 75/25 1.5 0.5 20 230 5100/0  2.0 0 20 60

The solutions of Table 4 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5, and a 10% chloroform solution ofa polysulfone resin having a number average molecular weight of 22000,commercially available from Aldrich Chemical Company, Inc., was thenspin coated thereon in the same manner.

When one solution was coated, the coated layer was allowed to stand atroom temperature for 1 minute, and the next solution was coated, inconducting the coating steps. The transparent coated glass substrate wasthen allowed to stand at room temperature for 1 day, and heat treated at100° C. for 10 hours to obtain a silica/polysulfone component-gradientfilm (40 μm in film thickness)

Infrared analysis was conducted on a surface of the resultingsilica/polysulfone component-gradient film. Peaks which belong to apolysulfone component such as peaks of a sulfone group at about 1150cm⁻¹ and 1330 cm⁻¹ are indicated, but there are no peaks which belong toa silica component.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a glass surfacethrough a film surface, and Si element was not detected on the filmsurface.

The results of the IR analysis and the Si elemental analysis by usingSEM indicate that a silica component is present in quantity near by theglass surface and a polysulfone component is not present, whereas, asilica component is not present near by the film surface and is almost apolysulfone component. Therefore, a compositional ratio of the silicacomponent to the polysulfone component is gradient in the range of from10/0 to 0/10, throughout the film.

Example 11

A mixed composition containing the PAS having a number average molecularweight of 6700 prepared in Preparation Example 5 and tetraethoxysilane(TEOS) in the ratio by weight shown in Table 5, was hydrolyzed inN,N-dimethylformamide (DMF) by using 1N aqueous hydrochloride at 50° C.to obtain solutions No. 1 to 5.

TABLE 5 Amounts of Components Employed for Preparing Wet Gel PAS/TEOSPAS TEOS DMF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7002 25/75 0.5 1.5 15 530 3 50/50 1.0 1.0 15 370 4 75/25 1.5 0.5 20 210 5100/0  2.0 0 20 50

The solutions of Table 5 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5, and a 10% dichloromethanesolution of a polyarylate resin commercially available from Unitika Ltd.as the trade name of “U-POLYMER”, was then spin coated thereon in thesame manner.

When one solution was coated, the coated layer was allowed to stand at50° C. for 30 minutes, and the next solution was coated, in conductingthe coating steps. The transparent coated glass substrate was thenallowed to stand at 50° C. for 3 days, and heat treated at 120° C. for10 hours to obtain a silica/polyarylate component-gradient film (50 μmin film thickness).

Infrared analysis was conducted on a surface of the resultingsilica/polyarylate component-gradient film. Peaks which belong to apolyarylate component such as a large peak of an ester group at about1740 cm⁻¹ are indicated, but there are no peaks which belong to a silicacomponent.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a glass surfacethrough a film surface, and Si element was not detected on the filmsurface.

The results of the IR analysis and the Si elemental analysis by usingSEM indicate that a silica component is present in quantity near by theglass surface and a polyarylate component is not present, whereas, asilica component is not present near by the film surface and is almost apolyarylate component. Therefore, a compositional ratio of the silicacomponent and the polyarylate component is gradient in the range of from10/0 to 0/10, throughout the film.

Example 12

A mixed composition containing the HPBS having a number averagemolecular weight of 3500 prepared in Preparation Example 6 andtetraethoxysilane (TEOS) in the ratio by weight shown in Table 6, washydrolyzed in THF by using 1N aqueous hydrochloride at 50° C. to obtainsolutions No. 1 to 5.

TABLE 6 Amounts of Components Employed for Preparing Wet Gel HPBS/TEOSHPBS TEOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7002 25/75 0.5 1.5 15 560 3 50/50 1.0 1.0 15 410 4 75/25 1.5 0.5 20 270 5100/0  2.0 0 20 130

The solutions of Table 6 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5. When one solution was coated,the coated layer was allowed to stand at room temperature for 30 minutesat room temperature, and the next solution was coated, in conducting thecoating steps. The transparent coated glass substrate was then allowedto dry at room temperature for 1 week to obtain a silica/polybutadienecomponent-gradient film (40 μm in film thickness)

Infrared analysis was conducted on a surface of the resultingsilica/polybutadiene component-gradient film. Peaks which belong to apolybutadiene component such as peaks of a C—H bond at about 1470 cm⁻¹and 2920 cm⁻¹ are indicated, but there are no peaks which belong to asilica component.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was ducted. Aconcentration of Si element gradiently reased from a glass surfacethrough a film surface, and element was not detected on the filmsurface.

The results of the IR analysis and the Si elemental analysis by usingSEM indicate that a silica component is present in quantity near by theglass surface and a polyarylate component is not present, whereas, asilica component is not present near by the film surface and is almost apolybutadiene component. Therefore, a compositional ratio of the silicacomponent to the polybutadiene component is gradient in the range offrom 10/0 to 0/10, throughout the film.

Example 13

A mixed composition containing the PES having a number average molecularweight of 3400 prepared in Preparation Example 7 and tetramethoxysilane(TMOS) in the ratio by weight shown in Table 7, was hydrolyzed in THF byusing 1N aqueous hydrochloride at room temperature to obtain solotionsNo. 1 to 5.

TABLE 7 Amounts of Components Employed for Preparing Wet Gel PES/TMOSPES TMOS THF 1N-HCl No. (ratio) (g) (g) (ml) (mg) 1  0/100 0 2.0 10 7202 25/75 0.5 1.5 13 570 3 50/50 1.0 1.0 15 420 4 75/25 1.5 0.5 18 270 5100/0  2.0 0 20 120

The solutions of Table 7 were coated on a glass substrate by using aspin coater in the order of No. 1 to 5. When one solution was coated,the coated layer was allowed to stand at room temperature for 30minutes, and the next solution was coated, in conducting the coatingsteps. The transparent coated glass substrate was then allowed to dry atroom temperature for 1 week to obtain a silica/polyestercomponent-gradient film (50 μm in film thickness)

Infrared analysis was conducted on a surface of the resultingsilica/polyethylene component-gradient film. Peaks which belong to apolyethylene component such as a large peak of an ester bond at about1730 cm⁻¹ are indicated, but there are no peaks which belong to a silicacomponent.

Cross section of the film was observed by using a scanning electronmicroscope (SEM). Macroscopic phase separation was not indicated, andgood fine structure was observed. Further, an elemental analysis of Siin the perpendicular direction to a surface of the film, was conducted.A concentration of Si element gradiently decreased from a glass surfacethrough a film surface, and Si element was not detected on the filmsurface.

The results of the IR analysis and the Si elemental analysis by usingSEM indicate that a silica component is present in quantity near by theglass surface and a polyester component is not present, whereas, asilica component is not present near by the film surface and is almost apolyethylene component. Therefore, a compositional ratio of the silicacomponent and the polyethylene component is gradient in the range offrom 10/0 to 0/10, throughout the film.

Comparative Example 1

2.0 g of a polycarbonate resin having a number average molecular weightof 36000, commercially available from Mitsubishi Engineering PlasticsK.K. as the trade name of “IUPILON”, was dissolved into 20 mL ofdichloromethane. The resulting solution was coated on a glass substrateaccording to the cast method to obtain a PC film (70 μm in filmthickness).

SEM observation was conducted on the resulting polycarbonate film. Theresults indicate that distribution of Si element greatly varies betweenthe glass and the PC. FIG. 3 is a SEM photograph which showscross-section of the PC film coated on the glass substrate, with Sielement concentration curve. In the drawing, 301 show a boundary part ofthe substrate and the film, and 302 shows a surface part of the film.

The results of heat shock test of this film were shown in Table 8.

Comparative Example 2

20 g of TEOS was dissolved into 20 mL of ethanol. 7.0 g of 1N aqueoushydrochloride was added to the solution, and hydrolysis was conducted.The solution was coated on a PC substrate by using the cast method toobtain a silica film (60 μm in film thickness).

SEM observation was conducted on the resulting silica film. The resultsindicate that distribution of Si element greatly varies between the PCand the silica. FIG. 4 is a SEM photograph which shows cross-section ofthe silica film coated on the PC substrate, with Si elementconcentration curve. In the drawing, 401 show a boundary part of thesubstrate and the film, and 402 shows a surface part of the film.

The results of heat shock test and chemical resistance test of this filmwere shown in Table 8 and 9.

Comparative Example 3

2.0 g of a polyphenylene ether resin having a number average molecularweight of 24000, commercially available from Nippon GE Plastics K.K. asthe trade name of “N-50-3181”, was dissolved into 20 mL of chloroform.The resulting solution was coated on a glass substrate according to thecast method to obtain a polyphenylene ether film (60 μm in filmthickness).

SEM observation was conducted on the resulting polyphenylene ether film.The results indicate that distribution of Si element greatly variesbetween the glass and the polyphenylene ether. The results of heat shocktest of this film were shown in Table 8.

Comparative Example 4

2.0 g of a polysulfone resin having a number average molecular weight of22000, commercially available from Aldrich Chemical Company, Inc., wasdissolved into 20 mL of chloroform. The resulting solution was coated ona glass substrate according to the cast method to obtain a polysulfonefilm (50 μm in film thickness)

SEM observation was conducted on the resulting polysulfone film. Theresults indicate that distribution of Si element greatly varies betweenthe glass and the polysulfone. The results of heat shock test of thisfilm were shown in Table 8.

Comparative Example 5

2.0 g of a polyarylate resin, commercially available from Unitika Ltd.as the trade name of “U-POLYMER”, was dissolved into 20 mL ofdichloromethane. The resulting solution was coated on a glass substrateaccording to the cast method to obtain a polyarylate film (50 μm in filmthickness).

SEM observation was conducted on the resulting polyarylate film. Theresults indicate that distribution of Si element greatly varies betweenthe glass and the polyarylate. The results of heat shock test of thisfilm were shown in Table 8.

Heat Shock Test

Heat shock test was conducted on the films prepared in Examples 1 to 11,and Comparative Examples 1 to 5. Test pieces (30×30 mm) of the filmswere heat treated at 170° C. or 120° C. in a drying oven for 30 minutes,and immediately they were transferred in a freezer of −20° C. andallowed to stand for 30 minutes. This cycle was repeated three times.Thereafter, the test pieces were visually observed.

In the test for the samples of Examples 1, 2, 5, 6, 9, 10, 11 andComparative Examples 1, 3, 4, 5, heating temperature was set to 170° C.As a result, the polycarbonate film of Comparative Example 1, thepolyphenylene ether film of Comparative Example 3, the polysulfone filmof Comparative Example 4, and the polyarylate film of ComparativeExample 5 were removed. Whereas, in the silica/polycarbonatecomponent-gradient films of Examples 1, 2, 5, 6, thesilica/polyphenylene ether component-gradient film of Example 9, thesilica/polysulfone component-gradient film of Example 10, and thesilica/polyarylate component-gradient film of Example 11, no change wasobserved.

In the test for the samples of Examples 3, 4, 7, 8, and ComparativeExample 2, heating temperature was set to 120° C. As a result, crackswere formed in the silica film of Comparative Example 2, and the filmwas removed. Whereas, in the silica/polycarbonate component-gradientfilm of Examples 3, 4, 7, and 8, no change was observed.

The results indicate that the materials with compositional gradient ofthe present invention have good heat shock resistance.

TABLE 8 Appearance of Film after Heat Shock Test Test Piece Heat Temp.Appearance C. Ex. 1 170° C. Film was removed, partially curved Ex. 1170° C. No change Ex. 2 170° C. No change Ex. 5 170° C. No change Ex. 6170° C. No change C. Ex. 2 120° C. Lots of cracks are formed, film wasremoved Ex. 3 120° C. No change Ex. 4 120° C. No change Ex. 7 120° C. Nochange Ex. 8 120° C. No change C. Ex. 3 170° C. Film was removed Ex. 9170° C. No change C. Ex. 4 170° C. Film was removed Ex. 10 170° C. Nochange C. Ex. 5 170° C. Film was removed Ex. 11 170° C. No change

Chemical Resistance Test

Chemical resistance test was conducted on the films prepared in Examples3, 4, 7, 8, and Comparative Example 2. 1 mL of an organic solvent wasdropped on test pieces (30×30 mm) of the films and allowed to dry.Thereafter, the test pieces were visually observed.

A PC board employed as a comparative example, was dissolved or whitenedby an organic solvent such as chloroform and acetone. The same resultsare shown on the silica film of Comparative Example 2, and the silicalayer was removed. The reason why the same results are shown on thesilica layer of Comparative Example 2, would be that the silica preparedby the sol-gel method is a porous material. Furthermore, interfacialstress would be caused in the silica layer due to shrinkage accompanywith the layer formation, and fine cracks would be formed throughout thesilica layer. Thereby, a solvent infiltrated through the pores, came tothe PC substrate, the PC substrate was solved, or deformed, and thesilica layer was broken and removed.

Whereas, no change of the appearance was observed on the films ofExamples 3, 4, 7, and 8, and excellent chemical resistance was shown.The reason of the excellent chemical resistance of the Examples bycomparison with Comparative Example 2 would be that the films of theExamples have component-gradient structure. That is, in Examples 3, 4,7, and 8, a silica component decreases from a film surface toward theinside, contrary a PC component increases. Therefore, the pores presentin the silica component also decreases, and the pores are interrupted bythe PC component, and no pores penetrate through the film. Furthermore,a large part of the PC component in the component-gradient films ofExamples 3, 4, 7, and 8 is covalently bonded to the silica component.Therefore, the PC component is hard to be deteriorated, and chemicalresistance is improved by synergistic effect of the two component.

The results indicate that the materials with compositional gradient ofthe present invention have good chemical resistance.

TABLE 9 Film Appearance after Chemical Resistance Test Organic PCSolvent board CEx. 2 Ex. 3 Ex. 4 Ex. 7 Ex. 8 methanol ◯ ◯ ◯ ◯ ◯ ◯ethanol ◯ ◯ ◯ ◯ ◯ ◯ acetone X X ◯ ◯ ◯ ◯ ethyl X X ◯ ◯ ◯ ◯ acetate THF XX ◯ ◯ ◯ ◯ dichloro- X X ◯ ◯ ◯ ◯ methane chloroform X X ◯ ◯ ◯ ◯ benzene XX ◯ ◯ ◯ ◯ n-hexane ◯ ◯ ◯ ◯ ◯ ◯ diethyl ◯ ◯ ◯ ◯ ◯ ◯ ether ◯: No change ofthe appearance was observed. X: Change of the appearance such asdissolution, swelling, clouding, discoloration, and removal, wasobserved.

What is claimed is:
 1. A process for preparing organic-inorganic hybrid polymer materials with compositional gradient comprising the steps of: providing a substrate having a surface; and applying plural layers of solutions or wet gels which comprises at least an organic polymer or a metal alkoxide, on the surface of the substrate, so that concentration of the organic polymer component, or of the metal oxide component in the resulting material, is continuously increased or decreased in the direction of thickness of the material.
 2. A process for preparing organic-inorganic hybrid polymer materials with compositional gradient comprising the steps of: (i) providing a substrate having a surface; (ii) applying thereon a solution or a wet gel which comprises at least an organic polymer or a metal alkoxide at a certain compositional ratio; (iii) applying thereon a solution or a wet gel which comprises at least an organic polymer or a metal alkoxide in altering a compositional ratio of the solution or the wet gel so that concentration of the organic polymer component, or of the metal oxide component in the resulting material, is increased or decreased in the direction of thickness of the material; (iv) repeating step (iii) at least one time.
 3. A process for preparing organic-inorganic hybrid polymer materials with compositional gradient comprising the steps of: (i) providing an organic substrate having a surface; (ii) applying thereon a solution which comprises an organic polymer; (iii) applying thereon a solution or a wet gel which comprises an organic polymer and a metal alkoxide at a certain compositional ratio; (iv) applying thereon a solution or a wet gel which comprises an organic polymer and a metal alkoxide in altering a compositional ratio of the solution or the wet gel so that concentration of the organic polymer component is lower than that of the previous step; (v) repeating step (iv) at least one time; and (vi) applying a solution or a wet gel comprising a metal alkoxide.
 4. A process for preparing organic-inorganic hybrid polymer materials with compositional gradient comprising the steps of: (i) providing an inorganic substrate having a surface; (ii) applying thereon a solution which comprises a metal alkoxide; (iii) applying thereon a solution or a wet gel which comprises an organic polymer and a metal alkoxide at a certain compositional ratio; (iv) applying thereon a solution or a wet gel which comprises an organic polymer and a metal alkoxide in altering a compositional ratio of the solution or the wet gel so that concentration of the metal alkoxide component is lower than that of the previous step; (v) repeating step (iv) at least one time; and (vi) applying a solution or a wet gel comprising an organic polymer. 